A nickname for a town in Williamstown, New Jersey. (South Jersey to be precise). This town has this name because it's known for it's dub (for you assholes, that don't know what dub is, look it up on urbandictionary.com!), and it's Dub-le U (W!) that the town's name starts with.

Friend One: Yo man, let's get fuckin' high tonight! Hook me up.
Friend Two: Alright man, we should head off to Dana's. She lives in Dubtown, ya know!